docs: def create_index_if_missing(self, index, settings=None):
          """Creates an index if it doesn't already exist.
  
          If supplied, settings must be a dictionary.
  
          :param index: the name of the index
          :keyword settings: a settings object or a dict containing settings
          """
          try:
              return self.create_index(index, settings)
          except IndexAlreadyExistsException as e:
              return e.result